> And what if you don't have a "default" plane as such. For example, OMAP3 > has one graphics plane and two video planes, and two output paths. Each > of the planes can be assigned to zero or one outputs. To accomodate this, > the design should allow for CRTCs without any scanout buffers.
Some TV type stuff is a bit like that - well there may be a scanout buffer but its on a protected hardware path and no part of the system except certain bits of hardware can touch it from decrypt to output connector. Clearly a scanout buffer isn't the only way to describe what a crtc is outputting and you need a somewhat more flexible handle including one you can acquire somehow to represent other objects like capture buffers, protected planes and live video merges. Alan
